Yes, the audio description and sign language features of the JW Player
certainly can enhance accessibility for people that want those
features. If you're just looking for a standard, accessible player,
there's not much difference between the ones we've discussed. But the
JW Player offers tremendous amounts of customization, skins, a very
cool display wizard
(http://www.longtailvideo.com/support/jw-player-setup-wizard), file
protection, playlists, plugins
(http://www.longtailvideo.com/addons/plugins) and many other features
that might be useful. Perhaps best of all, it's free and open source,
unlike the FLVPlayback and FLVPlaybackCaptioning which comes with
Flash CS4.